1. Field of the Invention
The present invention relates to a chain saw, more particularly to a chain saw with tool-free chain tension adjustment mechanism.
2. The Prior Arts
A chain saw is a kind of gasoline-powered portable tool, generally used for cutting wood and the like material. A conventional chain saw generally includes a chain with alternately disposed L-shaped cutting edges such that circular rotation of the chain around a longitudinal direction results in movement of the cutting edges against a wood piece. Traditionally, a flat tip screw driver is commonly used for tightening or loosening an adjustment screw so as to move a chain plate upon which the chain is trained thereon in order to achieve the appropriate tension of the chain.
It is inconvenient for the user to adjust the tension of chain with the use of the adjustment screw, since the latter may often get lost or in case when the same is not available nearby the user.
Moreover, in case the chain plate is disposed within the saw casing, it is relatively difficult and time-wasting for the user to align the through holes in the chain plate relative to the screw holes in the saw casing in order to tightening the chain plate securely relative to the saw casing.